1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
|
;;; Copyright © 2019 - 2022 Jakob L. Kreuze <zerodaysfordays@sdf.org>
;;;
;;; This program is free software; you can redistribute it and/or
;;; modify it under the terms of the GNU General Public License as
;;; published by the Free Software Foundation; either version 3 of the
;;; License, or (at your option) any later version.
;;;
;;; This program is distributed in the hope that it will be useful,
;;; but WITHOUT ANY WARRANTY; without even the implied warranty of
;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
;;; General Public License for more details.
;;;
;;; You should have received a copy of the GNU General Public License
;;; along with this program. If not, see
;;; <http://www.gnu.org/licenses/>.
(define-module (jakob dynamic capabilities comments)
#:use-module (ice-9 match)
#:use-module (jakob dynamic captcha)
#:use-module (jakob dynamic errors)
#:use-module (jakob dynamic util)
#:use-module (json)
#:use-module (squee)
#:use-module (srfi srfi-1)
#:use-module (srfi srfi-19)
#:use-module (srfi srfi-26)
#:use-module (web request)
#:use-module (web response)
#:use-module (web uri)
#:export (get-comments
get-comments-by-slug
put-comment
put-reaction
json->internal-comment
internal-comment?
internal-comment-id
internal-comment-name
internal-comment-subject
internal-comment-email
internal-comment-comment
internal-comment-url
internal-comment-publish-time
internal-comment-reactions))
(define conn (connect-to-postgres-paramstring "dbname=jakob_comments"))
(define-json-mapping <internal-comment>
make-internal-comment
internal-comment?
json->internal-comment <=> internal-comment->json
(id internal-comment-id)
(name internal-comment-name)
(subject internal-comment-subject)
(email internal-comment-email)
(comment internal-comment-comment)
(url internal-comment-url)
(publish-time
internal-comment-publish-time
"publish-time"
(lambda (x) (string->date x "~Y~m~d ~H~M~S.~N"))
(lambda (x) (date->string x "~Y-~m-~d ~H:~M:~S.~N")))
(reactions internal-comment-reactions))
(define (get-comments-by-slug slug)
"Internal function for querying the approved comments on a post
This interface exists for dynamically generating the comment view from Haunt."
(define (make-internal-comment~ . args)
(let* ((approved (first (take-right args 2)))
(approved (string->date approved "~Y~m~d ~H~M~S.~N"))
(reactions (last args))
(reactions (if reactions
(with-input-from-string reactions read)
'())))
(apply make-internal-comment
(append (drop-right args 2) (list approved reactions)))))
(let* ((query "SELECT id, name, subject, email, comment, url, approved, reactions
FROM comments WHERE slug = $1 and approved IS NOT NULL")
(result (exec-query conn query (list slug))))
(map (cut apply make-internal-comment~ <>) result)))
(define (get-comments request body)
"API endpoint handler for querying for the comments on a particular post
This is a wrapper around `get-comments-by-slug'."
(define (normalize-record record)
(json-string->scm (internal-comment->json record)))
(let* ((query-string (uri-query (request-uri request)))
(params (if query-string
(decode-form query-string)
'()))
(slug (assoc-ref params "p")))
(unless slug (panic "missing `slug' query parameter"))
(values '((content-type . (application/json)))
(scm->json-string
(list->vector
(map normalize-record (get-comments-by-slug (car slug))))))))
(define (put-comment request body)
"API endpoint handler for submitting a comment"
(define (valid-comment? form-data)
(and (assoc "slug" form-data)
(assoc "name" form-data)
(assoc "comment" form-data)
(or (assoc "captcha" form-data)
(and (assoc "captcha-alt" form-data)
(assoc "captcha-alt-id" form-data)))
(assoc "captcha-id" form-data)
(if (and (string? (assoc-value form-data "captcha-alt"))
(positive? (string-length (assoc-value form-data "captcha-alt"))))
(validate-proof-of-work!
(assoc-value form-data "captcha-alt")
(string->number (assoc-value form-data "captcha-alt-id")))
(validate-captcha!
(assoc-value form-data "captcha")
(string->number (assoc-value form-data "captcha-id"))))))
(define (insert-comment form-data)
(exec-query conn
"INSERT INTO comments (submitted, slug, name, subject,
email, url, comment)
VALUES (now(), $1, $2, $3, $4, $5, $6);"
(list (assoc-value form-data "slug")
(assoc-value form-data "name")
(assoc-value form-data "subject")
(assoc-value form-data "email")
(assoc-value form-data "url")
(assoc-value form-data "comment")))
(values (build-response
#:code 307
#:headers '((location . "https://jakob.space")))
(scm->json-string `((success . #t)))))
(let ((form-data (decode-form body)))
(unless (assoc "slug" form-data) (panic "missing param `slug'"))
(unless (assoc "name" form-data) (panic "missing param `name'"))
(unless (assoc "comment" form-data) (panic "missing param `comment'"))
(unless (assoc "captcha-id" form-data) (panic "missing param `captcha-id'"))
(unless (or (assoc "captcha" form-data)
(and (assoc "captcha-alt" form-data)
(assoc "captcha-alt-id" form-data)))
(panic "missing param `captcha' (or `captcha-alt' and `captcha-alt-id')"))
(if (and (string? (assoc-value form-data "captcha-alt"))
(positive? (string-length (assoc-value form-data "captcha-alt"))))
;; Alternate captcha fields specified; take the code path that validates
;; a proof-of-work.
(unless (validate-proof-of-work!
(assoc-value form-data "captcha-alt")
(string->number (assoc-value form-data "captcha-alt-id")))
(panic "proof-of-work not acceptable"))
;; Alternate captcha fields not specified, so take the normal code path
;; where we validate a captcha response.
(unless (validate-captcha!
(assoc-value form-data "captcha")
(string->number (assoc-value form-data "captcha-id")))
(panic "captcha incorrect")))
(insert-comment form-data)))
(define (add-reaction reactions reaction)
(with-output-to-string
(lambda ()
(let ((parsed (call-with-input-string reactions read)))
(write (acons-normalize reaction
(if (assoc reaction parsed) (+ 1 (assoc-value parsed reaction)) 1)
parsed))))))
(define (put-reaction request body)
(define (set-reactions id reactions)
(exec-query conn "UPDATE comments SET reactions = $1 WHERE id = $2"
(list reactions id)))
(define (comment-reactions id)
(let* ((query "SELECT reactions FROM comments WHERE id = $1")
(result (exec-query conn query (list id))))
;; It could be NULL, in which case we want the empty list instead.
(if (positive? (length result)) (or (caar result) "()") #f)))
(define (valid-reaction? form-data)
(and (assoc "id" form-data)
(assoc "reaction" form-data)))
(let* ((query-string (uri-query (request-uri request)))
(form-data (if query-string
(decode-form query-string)
'())))
(unless (assoc "id" form-data) (panic "missing param `id'"))
(unless (assoc "reaction" form-data) (panic "missing param `reaction'"))
(let ((id (assoc-value form-data "id"))
(reaction (assoc-value form-data "reaction"))
(reactions (comment-reactions id)))
(unless reactions (panic "no such comment"))
(set-reactions id (add-reaction reactions reaction))
(values '((content-type . (application/json)))
(scm->json-string `((success . #t)))))))
|
